OBD MPGuino gauge

[Keeper]

Hello, is it possible to see the wiring diagram for a graphical display Arduino.

Thank you.

[eimix]

Originally Posted by Keeper

Hello, is it possible to see the wiring diagram for a graphical display Arduino.

I found my drawings, i will paint them soon (tomorow probably).

That model of display you have?

[eimix]

if LED requires more current then Arduino +3.3V pin could provide - other +3.3V voltage regulator should be used.

Resistors could be similar - just output voltage should be between 3V-3.3V
If you have any other 5V->3.3V divider/converter - it could be used inplace of all resistors.

[Keeper]

AtMega1280-16au
and
1.8 "TFT Color LCD Module, Embedded LCD controller ST7735R

[eimix]

This one has its own voltage level converter.
And adafruit gives circuit for connecting it. you should follow it.

And it is with SD card support, so if you are going to use LCD only - not all pins are needed to connect (Card_cs and MISO).

And to my previous drawing

SCK = SCL
MOSI = SDA
TFT_CS = CS
D/C = RS
RESET = RESET

VCC = 5V
LITE = led power, but not sure.

[jorloujr]

My first post here and first of all I have to say: I´m very impressed ! OBDuino is an old dream coming true ;-)

I have it up and running in debug mode waiting for my cheap chinese "ELM327" to arrive, eager to plug it in my car ... ( Arduino Uno + LCD keypad shield )

There are a couple of things I´d like to modify to suit my needs and many other users I guess:

First and very important one: display fuel consumption in kilometers per liter [ km/l ] instead of liters per 100 km [ l/100 km ]. That´s the way people understand it in many countries around the world, it will be utterly useful. We must have this option, otherwise one of the most important OBDuino functions is useless to many people ...

Second: I´ve got a LCD keypad shield like this one:

w_w_w.dfrobot.com/index.php?route=product/product&product_id=51]LCD Shield For Arduino

(please remove the underlines from w_w_w ... I needed to do this to be able to publish the link, sorry)

I modified the code to suit the display pinout and it works fine but the keypad is of the analog kind and adapting the code is not so easy for a OBDuino noobie ... that shield is very popular among Arduino entusiasts, this mod would make life a lot easier by a great deal and would benefit many.

Is there anyone familiar with OBDuino code willing to help me out ?

[Wanderman]

Wow, that LCD is a beautiful thing.

I have an MPGuino (older style) works quite well with the simple injector pulse width and VSS signals on my 5.9L Chrysler TBI motor.

Since the engine computer is a 1990 it DOES have the earlier Chrysler implementation of the OBD1 protocol (and it's proprietary connector)

Any chance I can use a modified OBDGuino to access additional info??

Thanks!

Rich "The Wanderman"

[Keeper]

Hello
Could result in a complete circuit to connect the buttons to the Arduino Mega
Thank you.

[njakts]

I just can not understand, what is wrong with my car/board/me/software/hardware...
I think I have tried every code, every possible circuit, protocol etc... I have tried ELM327 and got so far that obduino is displaying zeros in all values, now I am trying to get it to work with mc33290.
I know my protocol is ISO
My el cheapo bluetooth adapter from ebay works like a charm on my android phone with Torque app
Torque app is saying that I have ISO9141-2 5baud protocol.
vehicle is Lexus IS200 year 2000 (yes it is is200,not is300, I am from europe)

I have an oscilloscope. would it be worth to connect it to car? I guess no, if obduino cannot get responce from car. Or does it and arduino is not reading it?

[njakts]

ok! success!

my obduino works with Elm327 and v193

 // ask protocol
  elm_command(str, PSTR("ATDPN\r"));
  // str[0] should be 'A' for automatic
  // set header to talk directly to ECU#1
  if(str[1]=='1')  // PWM
    elm_command(str, PSTR("ATSHE410F1\r"));
  else if(str[1]=='2')  // VPW
    elm_command(str, PSTR("ATSHA810F1\r"));
  else if(str[1]=='3')  // ISO 9141
    elm_command(str, PSTR("ATSH6810F1\r"));
  else if(str[1]=='6')  // CAN 11 bits
    elm_command(str, PSTR("ATSH7E0\r"));
  else if(str[1]=='7')  // CAN 29 bits
    elm_command(str, PSTR("ATSHDA10F1\r"));

had to uncomment this part to get it working...

now having problems with startup after eingne is been off. I think I will solve it with adding a delay on-off relay on power line